There are many applications requiring compressed gases that are not contaminated by lubricants utilized to lubricate a reciprocating compressor employed to compress the gas. Conventionally, compressors utilized to provide an oil or lubricant free compressed gas use oil scrapers and seals to prevent crankcase lubricant from migrating to an oil free zone wherein oil free gas is compressed and delivered.
Quite typically, the seals and/or scrapers, though highly efficient, are incapable of halting the flow of all of the oil or lubricant. In short, some oil or lubricant vapor inevitably migrates past the seals and contaminates the gas. While good compressor design will keep the oil contamination low, and filters downstream of the compressor may be utilized to separate the lubricant from the gas to provide a desired relatively free compressed gas product, it would be desirable to eliminate the need for downstream treatment and the maintenance that is associated therewith. The present invention is directed to solving the above problem.